Bit



Aug. 3, 1933. E, 4 RE 1,921,702

BIT

Filed Sept. 28, 1931 3 Sheets-Sheet 1 E. A. REED Aug. 8, 1933.

BIT

Filed Sept. 28

1931 3 Sheets-Sheet 2 Aug. 8, 1933. E. A. REED, 1,921,702.

- BIT Filed Sept. 28, 1931 3 Sheets-Sheet 3 EA. Heed faces of the Patented Aug. 8, 1933 Earl 'A. M. emery om.

Application September '28, 1931 Serial No. 565,595

9 Claims. (011255- 11):

My invention relates to deep well drilling apparatus and more particularly to improvements in drill bits such as, shown in my application, Serial No. 19i,a1s, n1ed May'26, 1927, Y

One object of my invention is to provide bit rollercutter and bushing in a unitary assembly which may be easily and securely mounted upon the supporting spindle of a drill head and detached therefrom.

Another object of the invention is to prevent slipping and chattering of the bushingupon the supporting spindle and the entrance; ofgrit and water therebetween and into the lubricating channels so as to minimize weaving of the bearing surfacesof the device.

Another. object'of the invention is to prevent the abrasive bearing circulating fluid, which is forced through the drill head; from forming eddies adjacent thereto, which would normally wear awayportions of the drill head.

A further object is to provide means forinsuring adequatelubrication of the bearing surroller cutter and bushing, particularly at the portions'of their greatest diameter 1 provide a method Fig. 4 is a plan view of the cutter bushing partly broken away; and

andrelative speed. I

A still further object of the invention is toof making the roller cutter and bushing assembly such that a unitary bushing is formed partially inside-a bearing cavity of the cutter so that all wear due to the rotation of the cutter takes place between thebushing and cutter and that chance separation of .the cutter and bushing is prevented. I v

Other objects and advantages of the invention will appear in the following description of the preferred embodiment of the invention shown in the attached drawings of which: Fig. 1 is afront elevation of a drill head assembly partly in section? w 2 is a side elevation thereof; Fig. 3 is a bottom .view of the drill head with the cutter assemblies removed;

iig. 5 is a sectional view of a modification of the device. 1 1 j Referring more particularly to the drawings, 10 represents the body portion of the drill head assembly. As shown in Fig. 3 the body portion is circular in horizontalcross section with flattened sides 11. The upper portion 12 of the body is smaller in diameter and is pro-. vided with'tapering threads 13 for attachment to ahollow drill pipe (not shown).

modification shown in Figs. 1 to 4, the body is other; Near the base is provided 1 with .an internal 'i le t "andha's its "elements parallel tocorresponding m mnmsnea' form jthe bushing ,in the bearing cavity 20 these grooves-are filled .with molten metal which fuses with the bushing provided "with depending legs 14 which terminatef. in substantially--co'nical spindles 15 which are adapted'to receive a cutter and bushing assembly indicated generally by 16.

Each cutter and bushing assembly 16 con- 0 sists of a' 'rollercutter 1'1 anda hardened'steel internalbushing 18." The cutter'l'l'ha's a sub gstantiahy conical/outer surface which is provided with a' plurality of cutting 19. Each cutterl'l I I providedwith an internal o5 frusto-c'onical' bearing cavity 20. diametrlcal elements of which are at right angles to 8,611.1

f the cutter the' cavity flange 21. The

.surface'jZZof saidfla'ngeywhich is remotefrom ithe base of t e cuttenfis' and itsfdiametricahelementsf are at less than a right angle to each other with also frustoconlcal their p x upon thesamecentral axisas the apex of the elements "of the bearing cavity 20"but op'po- 'sitely disposed.

Thesurface23 OfsaIdflang'e the based the cutter is frusto-conical.

elements of' the bearing cavity 20.

18 is' an int gral. member l having anouter bearing surface "conformingto and fitting the inner'begr-J- ting surface of thej roller cutter, and-isp'rovidedwithanexternal groove having frustoconical surfacest'oireceive the internal flange 6 21 of the cutter. Thebushing is provided with an internal substantially :Bemre" insertion into the bearingcayity 20,

the bushing consists of a plurality of sections.

Hrhe bushing is f'preferably diametrically divided into two oppositely disposed 26 and '2'7, and "twosmaller sections -28. As

clearly shown .atj29 in Fig.4, wherein oneof the smaller'sections' 28"has'been shown asfpar "tially broken away,*the'abuttingedges of the respective sections areinclined or beveled'such may be easily inserted that a smaller section 28 other sections edges are cut away, a at 30, to form grooves 31 whenthebu shing'is assembled. After insertion sections, preferably byanelectric welding" operation. The innercavity- 25 of the bushing is smooth conical surface fitting the spindle'15. r

"conical cavity 255 I which receives the conical spindle" 15 of the Hdrill head. 4

The diametrical elements of the spindle surface form right angles with each other and the axes of the spindles are positioned at an angle of with the axis of the drill head body 10. The base of the bushing 18 makes an angle of 45 with the axes of the drill head body and said base is provided with a flat circular surface 32. The surface 33 of the depending legs 14 of the drill head, which surrounds the spindles 15, is finished to a flat plane inclined 45 to the axis of the drill head to receive the base surface 32 of the bushing. As shown on Figs. 1 and 3 the depending legs 14 are provided with radially protruding portions 34, the lowersurface of which forms a continuation of the inclined plane surface 33.

The bushing 18 has formed in its inner surface a recess 35 to receive a retaining member 36 which is screw threaded into a recess 37 formed in the lower surface of the spindle 15. Also vformed in the inner surface of the bushing and diametrically opposite the recess 35 is a second recess 38 provided with screw threads 39 to receive the threaded end of a fastening element 40 which extends through'a transverse bore 41 in the leg 14. The fastening element 40 is procvided with a head 42 which is received in a recess 42a, concentric with the bore 41 and a washer 43 is positioned under. thehead of the fastening element 40.

The bore 41 -is provided with an internal annular groove 44 which is connected with an oil duct formed in the drill head and extends from the extreme upper end thereof. The upper end of drill head is provided with screw threads v46, forming attaching means for a lubricator (not shown). Transverse holes in the fastening element.40 register with the annular groove 44 and an axial bore 48 in the fastening element intersects said transverse holes. Said axial bore registers with a hole 49 extending through the bushing from thebottom of the recess 33,and concentric therewith, to provide an oil ductleading to the bearing surfaces of the bushing at a point near their outer periphery and greatest relative speed. Another bore 50 extending axially of the spindle 15 intersects the annular.

groove 44 and registers with an axial bore 51 in the bushing toform an oil duct to the central bearing surfacesof the bushing and cutter. The inner surface of the cutter is recessed at 52 to form a circular cavity adjacent the truncated portion of the bushing to provide a passage for the oil to the inner conical bearing surfaces.

In the device sh wn in Fig. 5 a modified form of ,bushing nd cutter assembly 16' is carried by a coni a1 spindle 15' the lower end 0t each leg 14' depending from the body portion 10 of the drill head assembly. As in the previously described modification, the cutter 17 is provided with cutting teeth 19 and is carried by a bushing 18. The cutter has an internal frusto-conical bearing cavity 20 provided with an internal flange 2-1", having a surface 22 remote from the base of the cutter which is frusto-conical and similar to the surface 22 of the previously describedmodification. The flange also has 'asurface 23' which is frusto-conical and has its elements parallel to cor responding elements In addition the flangehas a surface 23a which is perpendicular to the axis of the cutter and is adapted to abut an annular flange 18a formmg the base of the bushing 18.

The bushing 18 is an integral-member formed formed upon f' the bearing cavity 20'.

of sections which are welded together and tinished after their insertion into the bearing cavity of the cutter 17' in the same manner as the bushing 18 described above and has an outer bearing surface fitting and conforming to the inner bearing surface of the cutter. Thefiange 18a has a base surface 18b adapted to fit against an annular'plane surface 33' surrounding the spindle 15' and inclined at an angle of 45 to the axis of the drill head. By this structure the entrance of abrasive and water and loss of lubricant is practically prevented. The weight of the operating member and drill head presses the flat surface of the flange 18a against the flat base 23a of the roller cutter during operation thereof. to form an effective seal.

The bushing and cutter assembly 16 is retained upon the spindle 15 by means of retaining member 36 and locking member 40 as in the previously described modification and the spindle 15', bushing 20' and locking member 40 are provided with lubricating ducts 48, 49, 50, and 51, as in that modification.

The bore 41' through which the locking element 40 is inserted is enlarged at its upper portion so that, in the event the spindle 15'. be comes worn or an accurate fit between the bushing 18 and spindle 15' is not obtained in the field, shocks received by the cutter and bushing assembly will not' be sustained by the lockingelement 40 butwill be transmittedto the spindle 15'. r

The body portion of the drill head ,is also provided witli a longitudinally extending bore 53 through whichabrasivebearing water isforced;

Inclined holes 54 extend from the upper end of said bore to-the exterior of the body portion and inside the drill pipe (not shown). The lower end of .the': bore is enlarged and internally threaded to receive a, detachable" externally threaded nozzle 55 which h bore. The nozzle is provided ,witha converging bore 56 concenfi'ic with the bore 53" d of the same diameter at its larger end. The nozzle is further provided with, a cylindrical discharge bore 57 concentric with the bore 53 and of smaller diameter. The form of nozzle shown delivers the circulating fluid in a straight even stream, which does not form eddies adjacent the drill head which would rapidly wear'said head, due to the abrasive in the liquid. The straight downwardly directed stream is also effective to wash the cutter and remove material adhering between the teeth thereof.

In the use of drilling apparatus having rotary cutters, it is necessary to frequently provide the drill head with new cutters, as'the cutting teeth and bearing surfaces become worn. It will be noted that the cutters and bushings herein. described are adapted to be furnished to drillers as unitary assemblieswherein an integral bushing is retained in the cutter by an internal flange so that chance separation of the cutter and bushing is prevented before installation on the drill head or after such installation and during the drilling operation.

upon the spindle by merely slipping it axially of the drill head over the conical spindle and tightening the single fastening element 40. The flat base of the bushing fits snugly against the inclined plane on the drill head, effectually preventing any of the abrasive carrying circulating upon the leg 14" is threaded, into said The cutter and bushing assembly may be placed and securely retained liquid penetrating between the drill head and bushing is held firmly and non-rotatably against the spindle by the fasteningeiement 40 and the retaining member 36 such that slippingmnd;

chattering of the single piece bushing upon the spindle is prevented. Since the spindle is usually formed of cast steeland is of softer metal,

than the hardened steel bushing, I have ,dis-

covered means to-greatly lengthen the useful life of the spindle by applying ahard' surfacing tion of the cutters takes place between the renewable bushing andcutter, and-the portion of the, bushing adjacent the base thereof formsan eiIective wear plate integral with the bushing.

forpreventingcontact between the cutter and groove in said drill head. I

It will also be noted that the fastening element 40 serves as a means for supplying lubricant to the wearing surfaces adjacent the periphery the eof whereby centrifugal force, due to the rapi rotation of the cutter, causes the lubricant to flow outwardly, insuring an ade-,

quate supply at the outer edges. The cavity 52 at the center of the cutter allows the lubricant to readily flow an appreciable distance from the axis thereof such that centrifugal force is effective to cause the adequate lubrication of the more central portions of the wearing surfaces.

I claim as my invention: 7 1. The combination with a roller boring drill head, of a duct adapted to permit passage of lubricant downwardly a tainer to beconnected adjacent the top of said in a lateral said bore, diametrically through said locking plug and registering with said annular groove, an outlet duct for passage of lubricant extending centrally from the inner end of said locking plug'to and intersecting said diametrical ducts therein, a duct for the passage of lubricant through a bushing registering with the outlet of said outlet duct, and a second lubricant course comprising registering ducts leading from said annular lateral bore to the interior of a frusto-conical roller cutter adjacent its truncated apex through said spindle and bushing.

2. In a roller boring drill, the combination with a drill head having a downwardly extending frusto-conical cutter supporting spindle, of a roller cutter assembly adapted to be associated with and supported by said spindle, said cutter assembly comprising relatively rotatable cutter and bushing elements, the latter having an interior frusto-conical surface substantially matching the frusto-conicai surface of the spindle, and a locking element secured to said spindle and extending outwardly from the frusto-conical surface thereof, said bushing element having a recess adapted to receive said locking element, and a second locking element removably associated with said spindle and adapted to be screw threaded into a second recess in said bushing element. 1

3. The combination with a roller boring drill head having a spindle and a duct adapted to permit passage of lubricant downwardly from the top of said drill head to a lateral bore through the spindle of said drill head, a cutter assembly locking plug t and having an-iinlet, bushing and into the lubricating channels, The

,through said spindle,

from a lubricant con-' of a drill head disposed within said bore duct for-passage oflubri cant diametrically into said locking fplug and an outlet duct for ,.passage of lubricant extendingfrom the inner end of said locking'lplug to and intersectingsaiddiametric'al duct,\a. bushirig .mountedupon said spindle-and having a duct registering with said outlet duct for L the passage of,,lubricant through the bushing to the bearing surface thereof. I r 3 4. The combination withva roller boring drill, a a in i spindle 1 and a duct adapted to permit passage of lubricant downwardly from the top ofhsaid drillhead to a, lateral, bore a, cutter assembly locking plug disposed within said bore and, havingan inlet duct for passageof lubricant diametrically throughx said locking -plug,; said locking plug having ,an outletduct said diametrical duct for passage of lubricant, a frusto-conical bushing mounted upon said spindle and having a duct registering with said outlet duct for the passage of lubricant to the surface of said bushing, said spindle and said bushing having registering ducts leading from the surface of said bushing said lateral bore to adjacent its truncated apex. v

5. In a roller boring drill, the combination of a drill head having a cutter supporting spindle, a roller cutter assembly supported upon said spindle, relatively rotatable cutter and bushing elements, said spindle having a bore extending therethrough, a screw plug positioned in said bore and having screw-threaded engagement at its, inner end with said bushing for locking said bushing in non-rotatable position, ing of greater diameter than said screw plug, said screw plug having a longitudinal duct extending from its screw-threaded end and a transverse duct connecting said longitudinal duct with said bore, said drill head for supplying lubricant to said bore. 1

6. In a roller boring drill, the combination having spindle, dle, said spindle having a transverse bore extending therethrough, a screw in said bore and having its inner end terminating adjacent the inner surface of said cutter, said screw plug havin a portion within said bore of smaller diameter than said bore, said screw plug having a duct extending" longitudinally from its inner end for at least a portion of its length and also intermediate tudinal duct and the transverse bore of said spindle, said drill head havin a duct adapted to supply lubricant to said transverse bore.

7. In aaroller boring drill, the combination of a drill head having a cutter supporting spindle, a bushing non-rotatably mounted upon said spindle, said bushing having a conical outer bearing surface, a conical roller cutter having a conical inner bearing surface positioned upon said bore bea cutter. supporting a roller cutter journaled upon said spinhaving a transverse duct its ends, connecting; said longiu extendingfrom the inner -end ofsaidloeking plug to and intersecting said cutter assembly comprising havin a duct plug positioned 7 extending from its inner end and connectin with a source of lubricant for transmitting lubricantto the.outer portionof the bearing surface of said bushing.

8. In a roller boring drill, the combination of a drill head having a'cutter supporting spindle. a bushing non-rotatably mounted upon said spindle, saidv bushing 'having a conical outer bearing surface, a conical roller cutter having a conical inner bearing surface positioned upon said bushing for rotation relative thereto, a

screw plug positioned in a bore in said spindle I and having its inner end' terminating adjacent" spindles, with a lateral aperture, a removable locking locking element to permit said removable locking device due to wearing of and inwardly, a locking element projecting downwardly from the surface or each of said each of said'spindles being-provided element carried in each said lateral aperture, one end of which projects beyond the inner surface of each said spindles when in operative position, a frusto-conical roller cutter for each said spindles mounted upon a frusto-conical bushing, said bushing having --frusto-conical socket fitting said frusto-conical spindle and retained thereon by coaction of said locking elements with recesses in said bushing, said lateral aperture being enlarged above said removable upward movement of said bushing and spindle. 

